too many small butternut squash
I grew my butternut squash in planting pots, as you would for tomatoes. My crop doubled in quantity but were much smaller. No matter how much I watered and fed them, they wouldn't grow any bigger.
Certified GKH Gardening Expert
I'm wondering if they didn't have enough space. Butternut squash requires a lot of room. Also, too much fertilizer is detrimental. Here are the cultural needs for butternut squash: